Given the following balances, what is the most appropriate level of planning materiality for the 30 June 2020 audit of your client? (all amounts are in $'000) Sales: 1250 (2020); 1125 (2019); 1000 (2018) Profit: 112.9 (2020); 101.61 (2019); 90.32 (2018) Current assets: 29 (2020); 26.1 (2019); 23.2 (2018) O a. 0.3 O b. 6.2 O c. 11.3 O d. 12.5